Celestia and Luna always played together, but the elder often snuck away to the other kingdom and stayed. It started a day, a week away, then years. Luna didn't see her sister and her stays at home became less, until she stopped coming back.
In her sister's absence, Luna, since she was the eldest and powerfulest of them all, became protector of the Everfree. She still wondered about her sister every day when the sun rose and set, for that was Celestia's job, therefore had to be alive. Luna's was to start and end the night. She never knew until later that her sister longed to be in a land with ponies like herself and where her talent could be recognized, for that is what greed does. Unless most of it is dispatched, for it is okay to feel greed every once in a while, it can consume a creature. But she didn't know it, and was about to find out, because Lord Tirek had heard of this forest and it's odd and mysterious creatures. He wished to steal their magic
"There it is, ponies. The mysterious Everfree forest! The creatures it holds must have much power, for the pony told me so! Well, I say burn their home to the ground and find them!" Terik cried. Luna looked up from her flight and saw the ponies. "Who are they?" She growled.
Luna landed gracefully on a tree branch. "Come no further!" She boomed in her royal voice to the army.
Tirek looked up. "A alicorn…" He whispered. "Little pony! I can steal magic from any creature I want! Do you really think you can beat me?" He laughed. Luna narrowed her eyes. "The princess of the night shall give thouh one more chance!" She cried. "Leave." She growled. "How dare you oppose me, you winged brat!" Tirek spat. "You do not out rule me, you beast." Luna said. The lord looked to a guard. "Bring her to me." He said. Luna gasped. "Creatures of the shadows! Fight with me now!" She cried. The creatures arose and the army screamed. Timberwolves snarled, and a tatzlwurm burst out the ground, screeching. "Um…" A guard whispered. "ATTACK!" Lord Tirek screamed. The creatures ran and fought. Luna flew down and thrashed the ponies with her wings. She fired her magic and hit many. She laughed triumph but Tirek struck her to the ground. Luna screamed in pain and fell back, but first using a blast of magic at the lord. The princess saw that on his armor, was a pink star. She had seen that stone before and realized that was like the one Celestia had been wearing ever so long ago. She watched as the army left, their injured ruler in tow and she sighed, rubbing her burn. "Oh dear…" She sighed.
"As you can all see… I am dying." Tirek coughed, looking around at his servants. One was a teen alicorn with a flowing pink mane. "I need to chose a heir and a wife for my son, Sombra… I need one of you to destroy the childish teenager from the Everfree." The lord growled. "What is it's name, sir?" A pony asked, tentatively. "Her name is Luna… She calls herself a princess of the night…" Tirek coughed. Celestia's insides went cold. Maybe, she could become the queen, then the ponies would be happy again, right? But she didn't want to kill her little sister for it! It was for a good cause though, the ponies were miserable under Tirek and probably Sombra too! "Um, sir…" She piped up.
Later, Luna was sitting in her castle when there was a knock at the door. She opened it hesitantly. "Tia?" She gasped. "Oh Luna!" Celestia cried, hugging her sister. "Tia, I thought I-" Luna's sister put a hoof to her mouth. "We've got a lot to catch up on…" She whispered. Luna nodded. And so, the years faded away and Luna realized why she left and forgave her for what she did.
That night, Luna snored softly and Celestia smiled. She remembered this, it was like when she and her little sister slept together and played together and… No, she had a job to do. She sighed and breathed in, charging up her horn, one short blast and it would all be over. She growled at her weakness when she couldn't do it. "Little sister, I'm so sorry…" The princess whispered, realizing what she must do. She took a small vial out and used her magic. A bright blue, powerful magic drained from Luna as she slept and Celestia put a lot of it into a bottle. "I'll leave you with some… I'm sorry again, Luna." She said, planting a single kiss on her sister's cheek and matting that part of her fur with a tear. She ran off, ready to become Equestria's queen and rule over the citizens justly, or what she thought was.